1. Field of the Invention
The present invention relates to operation handles for use in vehicles, such as motorcycles, four- or three-wheeled buggies, snowmobiles, and water vehicles, and to grips mounted as these operation handles.
2. Description of the Related Art
In order to improve the design and grippability, it is desirable that a grip include a metal outer housing and an elastic resin portion, instead of being entirely made of rubber. For example, the resin portion is made of rubber, and is exposed from an opening, such as a hole (e.g., a slit) or a cutout, provided in the metal outer casing.
In particular, it is desirable that the resin portion slightly protrude from a metal surface portion of the casing. Front and rear surfaces of a cylindrical inner piece serving as a core of a grip, which is to be fitted in a mounting portion of a handle pipe or a throttle pipe, are covered with resin by molding. However, it becomes more difficult to press-fit the resin (rubber)-molded inner piece into the outer casing (in other words, to cover the inner piece with the outer casing) as the amount of protrusion of the resin portion from the metal surface portion (opening of the outer casing) increases.
For this reason, the protrusion cannot be achieved by such simple assembly using resin molding and fitting (covering), and it is difficult to commercialize grips at a low cost.